It uses a technology similar to photo printing to print the fine patterns on the mask onto the silicon wafer through exposure. There are many brands in mask aligner, which can be divided into step projection and scanning projection mask aligner according to different technical routes. The resolution is usually between 7 nanometers and several microns. High-end mask aligner is known as the most sophisticated instrument in the world, and there are 654.38+0.2 billion US dollars of mask aligner in the world.
High-end mask aligner is the flower of modern optical industry, and its manufacturing is very difficult, and only a few companies in the world can manufacture it. Foreign brands are mainly ASML in the Netherlands (the lens is from Germany), Nikon in Japan (high-end mask aligner, from which Intel once bought Nikon) and Canon in Japan.
Mask aligner performance index
The main performance indexes of mask aligner are: supporting substrate size range, resolution, alignment accuracy, exposure mode, light source wavelength, light intensity uniformity, production efficiency, etc.
Resolution: It describes the thinnest line precision that lithography can achieve. The resolution of lithography is limited by light source diffraction, so it is limited by light source, lithography system, photoresist and process.
Alignment accuracy: refers to the positioning accuracy of interlayer patterns during multi-layer exposure.
Exposure mode: contact approach, projection and direct writing.
Wavelength of exposure light source: divided into ultraviolet, deep ultraviolet and extreme ultraviolet regions. Light sources include mercury lamps and excimer lasers.
Alignment system: The manufacture of high-precision alignment system requires nearly perfect precision mechanical technology, which is also one of the technical difficulties that domestic mask aligner can't reach. Many American and German brands of mask aligner have special patented mechanical technology designs.
Refer to the above content: Baidu Encyclopedia-Mask Alignment Device